One BTC reaches ~$50 a coin, or major news networks start hyping this coin up, people who have no BTC will feel like they have missed this opportunity but are willing to jump on the next Bitcoin knock off (Google-coin, paypal-coin, Bitcoin v2.0, red-cross coins, "christcoins-with the pope's stamp of approval) as they are absolutely free to create and will start off at price 0. Or, some people might think it fun to mine for coins from their personal computers with a brand new currency.

I believe at least one of these e-currencies will thrive, it probably won't be bitcoin but at this point its still worth it to invest anyways given the large chances of failure and the mega-huge rewards of success. Does bitcoin have a first-mover advantage in staying dominant? I think people will have to ponder why the initial bitcoin miners deserve a huge chuck of the worlds wealth, what if they rather invest in "Red-cross bitcoins" where after the red-cross mined 1m Bitcoins then they went public or even worse threat to the original bitcoin, a religious bitcoin version.

If e-currencies do thrive, it might be divided over 100 bitcoin clients..............

Well, that problem always been in mind of humans. If the stone rings is so popular , why not to start stone romb`s ?If that hipe of paper worth so much, why not to start printing another papers ? And so one. Sometimes it even succeed. Mostly no.Every body free to try something better.

Definitely, I can imagine RedCrossCoins, and religious coins. How about GPLCoins, where some (central) server keeps a list of projects, say derived from packages in Debian/Fedora, and issues coins to people by counting lines of code being committed... The non-developer users of GPLCoins accept the idea and use exchanges to get the currency.Or even bigger - FreeCultureCoins, kind of like a global free culture flatrate. Same idea, central server counts downloads/viewer stats say on youtube or other sites, and issues coins for the uploaders. People that only consume need to buy FreeCultureCoins on exchanges. Shops accept payment in FreeCultureCoins because they like the idea.You can also build taxation into the system, who knows. As much as some people here seem opposed to taxes, with the computers/network running the currency code, you can build all sorts of things right into it. Some successful churches are asking their followers to pay 10% of their income to the church, not more, not less. Or maybe bitcoin stays the one and only, because first-mover advantage etc. And because it's so pure has none of these things.

And no matter how many forks/clones/improvements appear, people will still trade them. They will all just show up on exchanges and then we will find out about valuation.